Fluid motor valve construction



July 14, 1953 T, M HARDESTY 2,645,208

FLUID MOTOR VALVE CONSTRUCTION Filed June 27, 1949 3 Sheets-Sheet 1 Fig- J. T'Iz'g. JA

HIS ATTORNEYS July 14, 1953 r. M. HARDEsTY FLUID MOTOR VALVE coNsTRucTIoN mm l INVENTolL THOMAS MARVIN HARDESTY J IJ w w l u,

Filed June 27, 1949 H/S A TTOR/VEYS Patented July 14, 1953 UNITEDk STATES PATENT OFFICE FLUID MOTOR VALVECONSTRUCTION Thomas Marvin Hardesty, Crockett, Calif.

Application June 27, 1949, Serial No. 101,615 Y Y Claims.

The present invention has for its primary object the provision'of anovel and improved hydraulically operated pump assembly capable of use at the bottom of oil wells for pumping oil.

Among the other objects of my invention are:

(1) To provide a novel and improved hydraulically operated pump assembly for pumping oil from wells, which may utilize a portion of the pumped oil as the hydraulic operating iluid to the pump motor;

(2) To provide a novel and improved reciprocating type hydraulically operated pump assembly adapted for use in oil wells;

(3) To provide a novel and improved reciprocating type hydraulically operated pump assembly in ywhich the probability of the piston stopping on a dead center position is eliminated;

(4) To provide a novel and improved reciprocating type hydraulically operated pump assembly adaptable ior use in oil wells, and means in cooperation therewith for utilizing existing gas pressure in a well for assisting such pump assembly in pumping oil from a well.

vAdditional objects of :my invention will be brought out in the following description of a preferred embodiment of the same, taken in conjunction with the` accompanying drawings Figure 1 isV alongitudinal view in section through the upper portion of the pump assemblw" Figure la'is' a corresponding View in a plane normal to that of Figure l;

' Figure 2 is alongitudinal `view Vinr section throughthe intermediate portion of the'pump assembly and in the same plane as Figure 1; Y

' Figure v2a is a corresponding View in thesame plane asFigure la; y

Figure 3 is a'longitudinal View in section through thelower end portion of thepump assembly and in the same plane as Figure 2; Figure 3a is a corresponding view in the same plane as Figure 2a;

' Figure 4 is a view in section in the plane 4-4 of Figure 1a;

Figure 5 is a view in section in the plane 5--54 Figure 9 iS a1 View Y lsection the plane .9i-:9'4

the planrej'IlY--K` Figure 10 is a view in sectionin the plane IIl--I 0 of Figure 3a;

Figure ll is a view in section in the plane I I-I I of Figure 3a;

Referring vto the drawings for details of my invention in its preferred form, the same, fork convenience of analysisand description, may be divided into two parts, namely the pump I and the hydraulic motor 3- which drives such pump. Both portions, however, are intimately connected into a unitary pump assembly capable of beingv lowered -down to the bottom of a well for pumping oil therefrom to the surface; f i

The entire pump assembly in general is formed of a plurality of blocks, namely a head block -5,

an intermediate block 1 and a lower end block 9 held in spaced relationship longitudinally by c ylindrical casing sections II and I3 of similar dif-- ameter. This gives to the entire assembly a `uniform outside diameter free of projections, there-v by enabling the same to slide freely down a bore constitutes a part of the discharge for the oil pumped by the pump.

The lower end block is provided with an offcenter bore I9 extending longitudinally therethrough, in which is fitted an intake and dis- 1. charge ball valve assembly 2I involving a tube 23 its seating position.

From a location intermediate the ball valves, there is a connecting passage 33 to a central bore 35 in the lower endt block, connecting with the cylinder of the pump. The ball valve assembly is held in the off-center bore by an open nut 31 threaded into the lower end of said bore.

In the cylinder of the pump, is a piston 39 theintermediate block, into the motor end of Y the pump assembly.

The intermediate block, like the lower end block, is vsimilarlyiprovided with an oir-centen bore 43 therethrough; in which is mounted a.

similar intake-discharge ball Valve assembly 45 supported at its lower end by a closure plug 46. The bore has an intake passage connection 41 from the outside, while intermediate the ball Valves, a connecting passage 49 leads to the cylinder of the pump by way of the enlarged piston rod passage 42, whereby on the intake stroke of the pump, liquid will be suctioned into the upper end of the pump cylinder, and during the return stroke, will be discharged through the upper ball valve of the valve assembly 45.

The pump as thus described is a double acting pump adapted to suction in and discharge liquid on both the forward and return strokes of the pump piston.

If in certain designs, it is found necessary to use a smaller size ball valve assembly at the upper end of the pump by reason of the enlarged piston rod passage leading to the pump cylinder, it is contemplated that a plurality of such ball valve assemblies may be installed, each with its own connection to the passage leading to the pump cylinder.

At the motor end of the hydraulicV pump assembly, the aforementioned piston rod terminates in a piston which is slidably disposed in a cylinder 53 which itself is slidably disposed for limited movement within a fixed sleeve 55 of smaller diameter than the casing section and anchored in the head block at one end and in the intermediate block at the other end.

The cylinder is formed with a thicker wall section at each end, resulting in a shoulder 51 at each end facing the piston. Disposed Within the motor cylinder, intermediate each such shoulder and the piston, is a floating spring 59 to absorb the impact of the piston as it approaches the end of each stroke. The spring serves to accumulate the energy of such impact for sudden release against the adjacent shoulder of the cylinder.

The motor cylinder has an intake port 6| and a discharge port 63 at each end thereof, and the xed sleeve has openings 65 and 61 therein which are adapted to alternately expose the ports at each end of the cylinder as the cylinder moves relative to the sleeve within itsl permissible limits4 of movement.

In order to isolate the intake ports from the discharge ports of the motor cylinder, and provide for an intake passage 69 to such intake ports, and a separate discharge passage 1| leading from the discharge ports of the pump motor, the cylindrical space between the fixed sleeve 55 and the associated casing section is divided olf by radial partitions 13 and 15,` so located that the discharge from the upper end of the pump will enter the discharge passage 1| of the motor. As for the discharge from the lower half of the pump, a bore 16 longitudinally through the intermediate block, serves to complete a iiow path from the off-center bore |9 by way of the spacing I1 to the discharge passage 1|, where mingling of all the pumped uid with the exhaust uid of the motor can take place.

To feed the operating fiuid to the pump motor and at the same time to provide for discharge of the fluid from the pump assembly, the head block 5 is provided with diametrically disposed bores 11 and 1 9, one for-use as part of the intake passage, and the other for use as part of the discharge passage of the pump assembly.

At its upper end, the head block is provided with a capping pipe section 8| to which may be coupled, as by a coupling collar 83, the lowermost section of a pipe extending down from the surface. Concentrically disposed within this pipe, is a pipe 81 of smaller diameter, terminating at the head block in a flared section 89 which encompasses but one of the diametrcally disposed bores through the head block namely the bore 11. With such arrangement, one of the concentric pipes may be employed to feed operating fluid to the pump motor, while the other pipe may be employed to receive the combined discharge of the pump motor and pump for conduction to the surface a'bove.

The operating fluid pumped down to the well, thus will enter the exposed intake port in the cylinder and drive the piston ahead of it until the piston abuts the shoulder at the other end of the cylinder and forces the cylinder to a position where the aforementioned intake port is closed and the intake port at the far end of the cylinder is opened, with a similar` but reverse change taking place in connection with the discharge ports of the cylinder. In this manner, the pump motor is prepared for a return stroke and the operation is thus cyclically repeated to impart action to the pump at the lower end of the assembly.

As thus far described, however, the possibility prevails that the pump motor may stall at a dead center position, that is, with equal portions o'f' the intake ports exposed, whereby pump operations would necessarily cease. To preclude such possibility, and this constitutes an important feature of applicants invention, means are provided which will preclude shifting of the motor cylinder 53 until the piston impact pressure, as interpreted by the spring 59, reaches such value as to assure carrying the cylinder beyond the dead center position by the momentum thus imparted to it.

In accomplishing this objective, the cylinder is provided with a cylindrical stem 9| at its upper end which is slidably receivable in a longitudinal cylindrical recess provided for the purpose in the head block.

This cylindrical stem is provided with diametrically disposed grooves 93 at an intermediate location thereon, each such groove terminating in a substantially semi-circular recess 95 adapted to snugly receive a roller 91 associated with a. latching assembly 99 mounted within the head block. Each such latching assembly comprises a substantially cylindrical cage |0| open at each end but divided transversely by a partition wall |03. Within one end of the cage is mounted the aforementioned roller on a suitable shaft |05 carrying a ball bearing race on which the roller may freely rotate, and the cage is slidably positioned within a bore formed in the head block, the roller facing one of the grooves in the stem.

A recessed nut |01 encircling the outer end of,

the cage and threaded into the head block, provides with the cage, a chamber for a compression spring |09 which serves to resiliently urge the cage and roller in the direction of the stem, whereby the roller will be spring-urged into the groove at all times. The rating of the spring in each of the latching assemblies will of course determine the impact pressure which the piston must exert, to bring about a shift of the cylinder from one stroke-determining position to the other.

In order to preclude entrapment of liquid between the upper end of the cylinder and the head block, and between the upper end ofthe cylinder stem and the head block, which could block the upper stroke movement of the cylinder, I provide escape means for suchv liquid. In the upper end of the cylinder, this may take the form of a bore lll extending through the upper end wall of the cylinder, while a pair of diametrically dis-- posed channels I l3 running the full length of the longitudinal cylindrical recess in which the stem slides, effect a connection with the end of said recess and provide the escape means for any liquid which might otherwise be trapped above the end of this stem.

In some oil wells, there exists considerable gas under pressure, and my improved hydraulic pump assembly is so designed as to take advantage of any such gas pressure to assist the pump assembly in elevating the oil to the surface. This is accomplished through the very simple expedient of installing a ball valve preferably of the check valve type, in a passage which affords communication between the region of gas pressure and the discharge passage of the pump assembly.

Specifically and with reference to the drawings, such passage H5 is provided through the collar 83 in which passage is installed a ball check valve H1 adapted to open under gas pressure of a value which would afford some assistance in elevating the pump discharge to the surface above. In the absence of such gas pressure, the ball check valve will serve normally to block such passage against leakage of oil being discharged from the pump.

From the above description of my invention in its preferred form, it is apparent that the same will fulll all the objects previously recited, and while I have disclosed the same in its preferred form and in considerable detail, the specific embodiment illustrated and described is subject to alteration and modification without departing from the fundamental principles involved, and I accordingly do not desire to be limited in my protection to the specific details illustrated and described except as may be necessitated by the appended claims.

I claim:

l. A hydraulic motor comprising a cylinder, said cylinder having both an intake port and a discharge port at each end; a piston reciprocally disposed in said cylinder; means for alternately closing the ports at each end of said cylinder both with respect to each other and with respect to the corresponding ports at the other end of said cylinder, in timed relationship to the strokes of said piston, said means involving a sleeve in which said cylinder is relatively slidable within fixed limits, said sleeve having openings therein adapted to alternately expose the ports at each end, as such cylinder moves relative to said sleeve within vsuch limits of movement; means for causing movement of said cylinder relative to said sleeve in response to strokes of said piston said means including a resilient element intermediate each end of said sleeve and said piston; and releasable means resistively holding said cylinder against such relative movement in either direction until the piston impact pressure against an end of said sleeve by way of one of said resilient elements reaches a predetermined magnitude sufficient to overcome said releasable means whereby to permit said resilient element to cast said sleeve through its dead center position and effect the desired reversal of port openings.

2. A hydraulic motor comprising a cylinder, said cylinder having both an intake port and a discharge port at each end; apiston reciprocally disposed in said cylinder; means for alternately closing the ports at each end of said cylinder' both with respect to each other and with respect to the corresponding ports at the other end of said cylinder, in timed relationship to the strokes of said piston-said means involving a sleeve in which said cylinder is relatively slidable within fixed` limits, said sleeve having openings therein adapted to alternately expose ythe ports at each end, as such cylinder moves relative to said sleeve within such limitsY of movement; means for causing relative movement between said cylinder and said sleeve in response to strokes of said piston, said means including a shoulder on said cylinderat each end thereof and extending into the path of movement of said piston, and a coil spring `disposed between each such shoulder and said piston; and releasable means resistively holding said cylinder against such relative movement in either direction during compression of a spring until the piston impact pressure against a shoulder reaches a predetermined magnitude suiicient to overcome said releasable means,v

whereby to permit said spring to expand and cast said sleeve through its dead center position and effect the desired reversal of port openings.

3. A hydraulic motor comprising a cylinder, said cylinder having both an intake port and a discharge `port at each end; a piston reciprocally disposed in said cylinder; means for alternately closing the ports at each end of said cylinder both with respect to each other and with respect to the corresponding ports at the other end of said cylinder, in timed relationship to the strokes of said piston, said means involving a stationary sleeve in which said cylinder is slidable within xed limits, said sleeve having openings therein adapted to alternately expose the ports at each end, as such cylinder moves relative to said sleeve Within such limits of movement; means for causing movement o-f said cylinder relative to said sleeve in response to strokes of said piston, said means including a shoulder on said cylinder at each end thereof and extending into the path of movement of said piston, and a coil spring disposed between each such shoulder and said piston; and releasable means resistively holding said cylinder against movement in either direction during compression of a spring until the piston impact pressure against a shoulder reaches a predetermined magnitude suicient to overcome said releasable means, whereby to permit said spring to expand and cast said sleeve through its dead center position and effect the desired reversal of port openings.

4. A hydraulic motor comprising a, cylinder, said cylinder having both an intake port and a discharge kport at each end; a piston reciprocally disposed in said cylinder; means for alternately closing the ports at each end of said cylinder both with respect to each other and with respect to the corresponding ports at the other end Vof said cylinder, in timed relationship to the strokes of said piston, said means involving a sleeve in which said cylinder is relatively slidable within xed limits, said sleeve having openings therein adapted to alternately expose the ports at each end, as such cylinder moves relative to said sleeve within such limits of movement; means for causing relative movement between said cylinder and said sleeve in response to strokes of said piston, said means including a shoulder on said cylinder at each end thereof and extending into the path of movement of said piston, and

a coil spring disposed between each such shoulder' and said piston; and meansv for holding said cylinder against such movement in either direction until said piston approaches either extreme of its stroke and the corresponding coil spring is compressed.

5. A hydraulic motor comprising a cylinder, said cylinder having both an intake port and a discharge port at each end; a piston reciprocally disposed in said cylinder; means for alternately closing the ports at each end of said cylinder both with respect to each other and with respect to the corresponding ports at the other end of said cylinder, in timed relationship to the strokes of said piston, said means involving a stationary 15 sleeve in which said cylinder is slidable within fixed limits, said sleeve having openings therein adapted to alternately expose the ports at each end, as such cylinder moves relative to said sleeve within such limits of movement; means for causing movement of said cylinder relative to said sleeve in response to strokes of said piston, said means including a shoulder on said cylinder at each end thereof and extending into the path of movement of said piston, and ra coil spring disposed between each such shoulder and said piston; and means for holding said cylinder against such movement in either direction until said piston approaches either extreme of its stroke and the corresponding coil spring is compressed.

THOMAS MARVIN HARDESI-Y- References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 218,731 Gray Aug. 19, 1879 219,739 Kirsten Sept. 16, 1879 840,886 Wilkins Jan. 8, 1907 2,028,067 Heftye Jan. 14, 1936 2,200,071 Arnold May 7, 1940 2,258,493 Hull Oct. 7, 1941 2,331,151 Williams et al. Oct. 5, 1943 2,342,256 Duffyl Feb. 22, 1944 2,346,026 Henricks Apr. 4, 1944 2,364,600 Church Dec. 12, 1944 2,397,778 Cooper Apr. 2, 1946 

